Generally described, computing devices utilize a communication network, or a series of communication networks, to exchange data. Companies and organizations operate computer networks that interconnect a number of computing devices to support operations or provide services to third parties. The computing systems can be located in a single geographic location or located in multiple, distinct geographic locations (e.g., interconnected via private or public communication networks). Specifically, data centers or data processing centers, herein generally referred to as “data centers,” may include a number of interconnected computing systems to provide computing resources to users of the data center. The data centers may be private data centers operated on behalf of an organization or public data centers operated on behalf, or for the benefit of, the general public.
Service providers or content creators (such as businesses, artists, media distribution services, etc.) can employ a series of interconnected data centers to deliver content (such as web sites, web content, or other digital data) to users or clients. These interconnected data centers are sometimes referred to as “content delivery networks” (CDNs) or content delivery systems. Existing routing and addressing technologies can enable multiple data centers associated with a content delivery system to provide similar or identical content to client computing devices. In some instances, each data center providing a set of content may be referred to as a point-of-presence (“POP”). A content delivery system can maintain POPs over a wide area (or worldwide) to enable the system to efficiently service requests from clients in a variety of locations.
To provide access to content, server computing devices are generally associated with network addresses, enabling requests for communication with the server computing devices to be routed across a network. These network addresses are generally formed by a series of bits formatted according to a defined protocol, such as the Internet Protocol (IP) version four (IPv4) or version 6 (IPv6). Because network addresses may be difficult for humans to recognize and remember, CDNs can utilize resolution systems that function to resolve human-readable identifiers into corresponding network addresses. One example of such a resolution system is the Domain Name System (DNS), which functions to resolve domain names into corresponding network addresses.
Generally, DNS services and CDNs operate independently and according to differing protocols. For example, DNS requests from a client computing device are generally routed via the DNS protocol through multiple DNS components to a DNS service, where a network address corresponding to a domain name is returned via the DNS protocol. When a network address is obtained, the client computing device may then communicate with a server computing device associated with the network address (e.g., via the hypertext transport protocol, or “HTTP”). The respective processes of DNS resolution and communication with a network address are therefore generally logically distinct, such that a server computing device obtaining a request for content at a network address is unaware of a prior DNS resolution (if any) that facilitated the request.